1. Field of the Invention
The invention relates to a machine tool, in particular a handheld power tool, having an electrical drive motor.
2. Description of the Prior Art
For cooling the motor, handheld power tools with an electrical drive motor, such as angle sanders, have a fan wheel in the housing, which is driven by the motor and generates a cooling air flow that is guided through the housing of the handheld power tool. Since in operation of the handheld power tool in machining a workpiece, abrasive dirt particles are created that are carried via the cooling air flow into the interior of the housing, there is the risk of soiling of the drive motor as well as other parts of the machine tool that are located in the housing. The abrasive particles can become deposited in the housing and lead to wear at pole piece winding overhangs of the electrical drive motor, for instance, which can trip a short circuit with an attendant functional failure. Moreover, the dirt particles increase friction and impair the cooling capacity of the cooling air flow, thus reducing the heat dissipation.